This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Studies suggest that early treatment of infants diagnosed with an inherited disease provides the best survival and clinical outcomes, and that immature cell sources may be most efficient for transplant. These studies explore the fate of transplanted human cells from two differing sources and focus on overcoming bottlenecks by addressing essential issues related to human pluripotent cells for clinical transplantation.